i.e.

that if i know something, then for it to count as knowledge i must know that i know it (kk – know that i know)

i would say this is not the case

for example, say someone goes into an exam, and answers everyting, and when outside is asked, ‘how did you think it went?’ honestly replies. ‘well it was a tough exam, and im not sure if i did well.’

later it turns out they have aced the exam, with an A++ result

well we would say, yeah they knew the subject, yet they are unsure that they know it, breaking the kk principle

haveing said that, there must be a concept stronger than knowledge then, perhaps we should reserve the name ‘certainty’ for it. where we are somehow sure of what it turns out we know.

there may be a further distinction to make between ‘certain’ and ‘demonstrably certain’ where not only are you sure, but you can demonstrate the basis of the certainty. although in practice, that is actually very rare indeed.

listen to me, my son, said the devil
while he placed his hand upon my head

Edgar A. Poe
from “Silence-a fabel”